LRESULT CALLBACK
WndProc (HWND hwnd, UINT iMsg, WPARAM wParam, LPARAM lParam) {
     switch (iMsg) {
		// other message handlers
		case WM_DEVICECHANGE:	
			switch(wParam) {
				case DBT_DEVICEARRIVAL:
					// here handle only arrivals
					break;
				case DBT_DEVICEREMOVECOMPLETE:
					// here handle only removals
					break;
				case DBT_DEVNODES_CHANGED:
					// here handle changes
					break;
			}
			break;
		// other message handlers
     }
     return 0;
}

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mosch